90% of people don’t own a VOM or know how to use it, so we are talking about 10% of people could benefit. Of that 10%, 9% are technicians who know that it is faster, easier and cheaper to just replace the plug. Looks like a guy looking for U-tube advertising dollars.
If you would read my post you would see I said replace the plug. Never said anything about any other parts. A good repair man knows how to read and understand the printed word. I guess you think I’m a pretty poor repairman and you are entitled to that opinion, but I disagree.
Using an ohmmeter to test a spark plug is pretty much useless. When i worked at a small airport one summer i tested spark plugs. After the plugs were cleaned you put them in a machine that pressurized the plug to a few hundred PSi then you turn up the voltage and measure how much voltage it takes to fire the plug and checked the plug doesn't arc across the insulator.
I think you are misinterpreting what Rivets said. He just replaced the plug like most techs and the reasoning is because it is the cheapest route.Ummm. So your method is guessing and supposing what the problem might be, preferring that to testing your theory and knowing for sure?
-Could be a bad spark plug --- replace it.
-Could be a dirty carb ----replace it.
- Could be a bad coil ----replace it.
And so on.
In the furnace repair bus I was part of, this kind of guessing was the mark of a poor repairman.
The good repairman had a extensive skills in how to test possibly defective parts, and tended to work his way through a series of tests until he was confident he had identified the actual problem.
I had quite a bit of experience with repairmen of the poor type because I often followed along behind them when their repairs didn't actually fix the problem, which recurred.
I do note, however, that B&S maintenance requirements often specify replacing spark plugs after a few hundred hours of machine operation as a matter of routine maintenance. I suppose that would justify routine replacement of spark plugs, but you still aren't really going to know if the plug was the problem or whether you should look further.
Ummm. So your method is guessing and supposing what the problem might be, preferring that to testing your theory and knowing for sure?
-Could be a bad spark plug --- replace it.
-Could be a dirty carb ----replace it.
- Could be a bad coil ----replace it.
And so on.
In the furnace repair bus I was part of, this kind of guessing was the mark of a poor repairman.
The good repairman had a extensive skills in how to test possibly defective parts, and tended to work his way through a series of tests until he was confident he had identified the actual problem.
I had quite a bit of experience with repairmen of the poor type because I often followed along behind them when their repairs didn't actually fix the problem, which recurred.
I do note, however, that B&S maintenance requirements often specify replacing spark plugs after a few hundred hours of machine operation as a matter of routine maintenance. I suppose that would justify routine replacement of spark plugs, but you still aren't really going to know if the plug was the problem or whether you should look further.
If anyone wants to be a quality troubleshooting small engine mechanic and not a parts swapper get one of these
Aviation Spark Plug Testers 110V And 220V | Aircraft Spruce
Aviation Spark Plug Testers 110V And 220V Designed to clean and test all 14mm & 18mm massive and fine-wire electrode aviation sparkplugs.www.aircraftspruce.com
It is a time issue. It cost the same labor wise to install a new plug as opposed to the old plug. Just put a spark tester on a engine this morning and the tester said the plug was firing. Pulled the plug and it was wet. Installed new plug and it fired right up. Would crank all day long with the plug that the spark tester said was firing but wasn'tI appreciate the explanations.
The consensus is that using an ohmmeter to test spark plugs is a waste of time.
Replacing the spark plug as a matter of routine is the preferred option for dealing with the spark plug issue. This is supported by the common B&S specification to replace the spark plug after 100 hours of engine operation.
I have rarely changed out spark plugs myself. I'll have to change that practice.
Thanks for the help and advice.
It is a time issue. It cost the same labor wise to install a new plug as opposed to the old plug. Just put a spark tester on a engine this morning and the tester said the plug was firing. Pulled the plug and it was wet. Installed new plug and it fired right up. Would crank all day long with the plug that the spark tester said was firing but wasn't
Seattle. All the inline spark testers will show false positives in some cases. Also grounding the plug and seeing spark doesn't mean that the plug is firing under compression or in some cases the spark will jump from the center electrode to the side of the plug instead just jumping the gap even though it is narrower than the path the spark is taking will not fire under load.
Had a 24 plug shop pack of J19LM that all failed within 10 minutes of first run after installationThanks for the additional comments.
My experience as a furnace repairman was that a part was MOST LIKELY to be bad when it was new, right out of the box.
Have you found new spark plugs that were no good, or does the manufacturer's inspection/quality control eliminate that?
Grounding the plug and looking for spark is more of a verification that the ignition system is working..
There are a lot of pure garbage videos on youtube. In most cases, you have to already know what you're doing to be able recognize garbage when you see it.
Bummer there. How did they fail? internal short?Had a 24 plug shop pack of J19LM that all failed within 10 minutes of first run after installation
Appeared to fail open. Install plug, start engine, and within 3-10 engine would die. Check for fire and find none, replace plug and repeat. Spring tune up period so customer would return mower saying it just died. Multiple engines over a few week period.Bummer there. How did they fail? internal short?
I wonder if those were part of the ones that were the first batches out of Mexico. They had problems when they first opened the plant there.Appeared to fail open. Install plug, start engine, and within 3-10 engine would die. Check for fire and find none, replace plug and repeat. Spring tune up period so customer would return mower saying it just died. Multiple engines over a few week period.
Which means someone dropped them probably in shipping.Had a 24 plug shop pack of J19LM that all failed within 10 minutes of first run after installation
If they were shorted they would ALL work.Bummer there. How did they fail? internal short?
And today is 28,000,000 plugs later. Probably safe to rule out Mexico.I wonder if those were part of the ones that were the first batches out of Mexico. They had problems when they first opened the plant there.
By internal short i meant the plug arcs internally from the center conductor to the metal shell.Inline spark testers showing false positives LOL
If they were shorted they would ALL work.
slomo
That was also my thought, but that styrofoam packing box that Champion shop packs come in would of had some serious damage.Which means someone dropped them probably in shipping.
slomo
Remember they have ceramic insulators. Either a bad batch or they were dropped. One thing for sure is they went like hot cakes.That was also my thought, but that styrofoam packing box that Champion shop packs come in would of had some serious damage.
Electrically speaking, that is not a short. Shorts are caused by excessive current, blow breakers and burn wires and houses down. I know what you meant. Just busting your chops LOL.By internal short i meant the plug arcs internally from the center conductor to the metal shell.
You can't look at a spark plug and tell if it is good or not. You need special equipment to test a spark plug. For $2 it is more expedient for a shop to replace a plug and see is that solves a spark issue rather than looking for a high tension spark plug tester. Some of us buffons running small engine shops may have some skills other than mowers. I serviced printing equipment for 40 years. Some of it multi million dollar systems with some single repair parts costing thousands of dollars. You better be able to troubleshoot logically or else look for another job
when aircraft were in for scheduled maint the plugs were removed, cleaned and tested. If they failed they wefe replaced. Some radial engines have 36 cylinders with two plugs per cylinder and 2 or 4 engines. With 2 engines that is 144 plugs and at close to $10 a plug aircraft owners don't want to drop an extra $1500 for plugs. Yes we tested and documented new plugs.
If you are talking about aircraft plugs no new ones failed but you have to document everything on the annual. When a plug went into a plane it has documentation. Hell, i had to document when i put nitrogen in struts and air in tires.How often did a new plug fail testing?
Had an engine years ago that you would only do that once. You grab the plug wire and I will turn the flywheel very very slowly. Until it clicked and you got hit with a full magneto discharge.How to test a spark plug the CHEAP WAY.
1. remove the sparkplug from your engine.
2. reconnect the spark plug wire to the spark plug
3. Grab a neighborhood kid off their bicycle and have them hold the end of the spark plug.
4. it's best for them to remove their shoes to have a good ground
5. pull the starter rope, if they don't holler you ain't got no spark, if they grimace or just whine... You have weak spark, if they jump back and cry you have good spark and continue troubleshooting. Also the higher they jump and the louder scream, the more powerful your spark is.
Must've had an impulse coupling.Had an engine years ago that you would only do that once. You grab the plug wire and I will turn the flywheel very very slowly. Until it clicked and you got hit with a full magneto discharge.
When I was in college, I worked PT for a guy who owned a fleet of WWII bombers, patrol planes, and freighters (Douglas A/B-26, Lockheed PV-2, R5D, and Douglas DC-7) used as air tankers. Most had either the P&W R2800 or R2000; the -7's had R3350's. IIRC, the bottom cylinders used dual wire electrode plugs. Those Pratts ran so smooth you could read the engine data plates from the pilot's seat with the engine running. Of course, the cowls had to be off.If you are talking about aircraft plugs no new ones failed but you have to document everything on the annual. When a plug went into a plane it has documentation. Hell, i had to document when i put nitrogen in struts and air in tires.
The airport i worked at one summer specialized in servicing turboprob Aero Commanders and planes with radials. Since i was a high school kid i changed oil, serviced spark plugs, checked tire and strut pressures and washed planes. Saw a few R2800's and R2180's and others i can't remember. We did regular maint on a Howard 500. Nothing like an oil change that requires a 55 gallon barrel of Aeroshell 40wt. Per engine. That was almost 50 years ago.When I was in college, I worked PT for a guy who owned a fleet of WWII bombers, patrol planes, and freighters (Douglas A/B-26, Lockheed PV-2, R5D, and Douglas DC-7) used as air tankers. Most had either the P&W R2800 or R2000; the -7's had R3350's. IIRC, the bottom cylinders used dual wire electrode plugs. Those Pratts ran so smooth you could read the engine data plates from the pilot's seat with the engine running. Of course, the cowls had to be off.
When I was in college, I worked PT for a guy who owned a fleet of WWII bombers, patrol planes, and freighters (Douglas A/B-26, Lockheed PV-2, R5D, and Douglas DC-7) used as air tankers. Most had either the P&W R2800 or R2000; the -7's had R3350's. IIRC, the bottom cylinders used dual wire electrode plugs. Those Pratts ran so smooth you could read the engine data plates from the pilot's seat with the engine running. Of course, the cowls had to be off.
Worked all 4 years of high school as a pinspotter mechanic at a small bowling alley. Went to the AMF school for 2 weeks when i was 14 and got certified. During the summers i worked other jobs. One summer it was at an airport in the maint hanger. Even though i wasn't an A&P mechanic they let me touch tools. Charlie Wells ran the maint hanger and he liked me. Used to take me to lunch in his 33 Duesenberg. The other high school guys swept floors and washed planes and painted stuff. After HS spent 3 years gathering intelligence for the NSA on on East Germans and Soviets in Berlin while I was a teenager. After than came home and worked 40 years fixing copiers and printers. Been running a mower shop on the side since the early 90's. I enjoy working on engines and equipment. I am retired so now the mower shop is pretty much full time.Howcum you aircraft mechanics are working on lawnmowers these days?
Worked all 4 years of high school as a pinspotter mechanic at a small bowling alley. Went to the AMF school for 2 weeks when i was 14 and got certified. During the summers i worked other jobs. One summer it was at an airport in the maint hanger. Even though i wasn't an A&P mechanic they let me touch tools. Charlie Wells ran the maint hanger and he liked me. Used to take me to lunch in his 33 Duesenberg. The other high school guys swept floors and washed planes and painted stuff. After HS spent 3 years gathering intelligence for the NSA on on East Germans and Soviets in Berlin while I was a teenager. After than came home and worked 40 years fixing copiers and printers. Been running a mower shop on the side since the early 90's. I enjoy working on engines and equipment. I am retired so now the mower shop is pretty much full time.
For the same reason that B & S is filing a chapter 11 and the dud management from McDonald Douglas has sent Boeing to the wall.Howcum you aircraft mechanics are working on lawnmowers these days?
I'm not. I never got the A&P or IA (inspector) license a real aircraft mechanic is required to have. I did a lot of work on airplanes, both other people's and my own, but all my work had to be inspected and signed off by an A&P or IA.Howcum you aircraft mechanics are working on lawnmowers these days?
Well......spending 5 nights a week during all 4 years of HS and spending all your free time working on cars sort of makes you a dick socially in HS. If you can fix machines then you can fix machines. If you can't you can't. Other than the 2 weeks at the AMF school everthing else is self learned. Biggest difference in the service industry is do you interact with customers and what level. Do you have the mechanical skills and the customer skills? Nothing like standing in front of a vice president and telling him the printer will be down another 24 hours because FedEx lost the part you ordered and the machine has already been down for a day and he is telling you they lose $50,000 in production every 8 hr shift the printer is down. You better be able sing and dance at the same time. Machines are easy, people not so much.So----
You've worked in a number of different repair specialties.
How much do you find being a repairman involves skills that readily translate to different specialties, and how much do you find that each specialty involves distinctly different skills?
A good comparison might be contrasting doing engine repairs vs doing bowling equipment repair or printer and copier repair?
And......nobody has the equipment to actually test a plug anyway.If I had an employee that wasted any time testing a spark plug, I would fire him.